/*
Copyright (C) 1996-1997 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 3
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// world.c -- world query functions

#include "quakedef.h"

/*

entities never clip against themselves, or their owner

line of sight checks trace->crosscontent, but bullets don't

*/


typedef struct moveclip_s
{
	vec3_t		boxmins, boxmaxs;// enclose the test object along entire move
	float		*mins, *maxs;	// size of the moving object
	vec3_t		mins2, maxs2;	// size when clipping against mosnters
	float		*start, *end;
	trace_t		*trace;
	int			type;
	edict_t		*passedict;
} moveclip_t;


int SV_HullPointContents (hull_t *hull, int num, vec3_t p);

BOOL SV_EdictRotated (edict_t *ed, float *check)
{
	// the world never rotates (this is important as e3m3 has angles set!!!)
	if (ed == sv.worldedict) return FALSE;

	// only SOLID_BSP entities are checked
	if (ed->v.solid == SOLID_BSP)
	{
		// check can be either angles or avelocity and if any are non-zero it rotates
		if (check[0]) return TRUE;
		if (check[1]) return TRUE;
		if (check[2]) return TRUE;
	}

	// edict is not rotated
	return FALSE;
}


/*
===============================================================================

HULL BOXES

===============================================================================
*/


static	hull_t		box_hull;
static	mclipnode_t	box_clipnodes[6];
static	mplane_t	box_planes[6];

/*
===================
SV_InitBoxHull

Set up the planes and clipnodes so that the six floats of a bounding box
can just be stored out and get a proper hull_t structure.
===================
*/
void SV_InitBoxHull (void)
{
	int		i;
	int		side;

	box_hull.clipnodes = box_clipnodes;
	box_hull.planes = box_planes;
	box_hull.firstclipnode = 0;
	box_hull.lastclipnode = 5;

	for (i = 0; i < 6; i++)
	{
		box_clipnodes[i].planenum = i;

		side = i & 1;

		box_clipnodes[i].children[side] = CONTENTS_EMPTY;

		if (i != 5)
			box_clipnodes[i].children[side ^ 1] = i + 1;
		else box_clipnodes[i].children[side ^ 1] = CONTENTS_SOLID;

		box_planes[i].normal[i >> 1] = 1;
	}

}


/*
===================
SV_HullForBox

To keep everything totally uniform, bounding boxes are turned into small
BSP trees instead of being compared directly.
===================
*/
hull_t *SV_HullForBox (vec3_t mins, vec3_t maxs)
{
	box_planes[0].dist = maxs[0];
	box_planes[1].dist = mins[0];
	box_planes[2].dist = maxs[1];
	box_planes[3].dist = mins[1];
	box_planes[4].dist = maxs[2];
	box_planes[5].dist = mins[2];

	return &box_hull;
}



/*
================
SV_HullForEntity

Returns a hull that can be used for testing or clipping an object of mins/maxs
size.
Offset is filled in to contain the adjustment that must be added to the
testing object's origin to get a point to use with the returned hull.
================
*/
hull_t *SV_HullForEntity (edict_t *ent, vec3_t mins, vec3_t maxs, vec3_t offset)
{
	model_t		*model;
	vec3_t		size;
	vec3_t		hullmins, hullmaxs;
	hull_t		*hull;

	// decide which clipping hull to use, based on the size
	if (ent->v.solid == SOLID_BSP)
	{
		// explicit hulls in the BSP model
		if (ent->v.movetype != MOVETYPE_PUSH)
		{
			Sys_Error ("SOLID_BSP without MOVETYPE_PUSH");
			return NULL;
		}

		model = sv.models[(int) ent->v.modelindex];

		if (!model || model->type != mod_brush)
		{
			Sys_Error ("SOLID_BSP with a non bsp model");
			return NULL;
		}

		Vector3Subtract (size, maxs, mins);

		if (size[0] < 3)
			hull = &model->hulls[0];
		else if (size[0] <= 32)
			hull = &model->hulls[1];
		else hull = &model->hulls[2];

		// calculate an offset value to center the origin
		Vector3Subtract (offset, hull->clip_mins, mins);
		Vector3Add (offset, offset, ent->v.origin);
	}
	else
	{
		// create a temp hull from bounding box sizes
		Vector3Subtract (hullmins, ent->v.mins, maxs);
		Vector3Subtract (hullmaxs, ent->v.maxs, mins);
		hull = SV_HullForBox (hullmins, hullmaxs);

		Vector3Copy (offset, ent->v.origin);
	}

	return hull;
}


/*
===============================================================================

ENTITY AREA CHECKING

here we accelerate collision checking for larger maps by building more areanodes
this can be a LARGE performance improvement (> 10% worst-case in marcher)

===============================================================================
*/

#ifdef NEW_AREANODES
typedef struct areanode_s
{
	int		axis;		// -1 = leaf node
	float	dist;
	struct areanode_s	*children[2];
	link_t	trigger_edicts;
	link_t	solid_edicts;
} areanode_t;

static	areanode_t	*sv_areanodes = NULL;
int num_areanodes = 0;


areanode_t *SV_CreateAreaNode (int depth, vec3_t mins, vec3_t maxs)
{
	areanode_t	*anode;
	vec3_t		size;
	vec3_t		mins1, maxs1, mins2, maxs2;

	anode = (areanode_t *) mapPool->Alloc (sizeof (areanode_t));
	num_areanodes++;

	ClearLink (&anode->trigger_edicts);
	ClearLink (&anode->solid_edicts);

	Vector3Subtract (size, maxs, mins);

	// don't get too small
	if ((size[0] < 1000 && size[1] < 1000) ||
		(size[0] < 1000 && size[2] < 1000) ||
		(size[1] < 1000 && size[2] < 1000))
	{
		anode->axis = -1;
		anode->children[0] = anode->children[1] = NULL;
		return anode;
	}

	if (size[0] > size[1])
		anode->axis = 0;
	else anode->axis = 1;

	anode->dist = 0.5 * (maxs[anode->axis] + mins[anode->axis]);

	Vector3Copy (mins1, mins);
	Vector3Copy (mins2, mins);
	Vector3Copy (maxs1, maxs);
	Vector3Copy (maxs2, maxs);

	maxs1[anode->axis] = mins2[anode->axis] = anode->dist;

	anode->children[0] = SV_CreateAreaNode (depth + 1, mins2, maxs2);
	anode->children[1] = SV_CreateAreaNode (depth + 1, mins1, maxs1);

	return anode;
}


void SV_ClearWorld (void)
{
	num_areanodes = 0;
	SV_InitBoxHull ();
	sv_areanodes = SV_CreateAreaNode (0, sv.worldmodel->mins, sv.worldmodel->maxs);
	Con_Printf (PRINT_SAFE, "Created %i areanodes\n", num_areanodes);
}
#else
// the new areanode code has entity interaction bugs so we don't use it
// oh well, guess we'll fix it sometime, but for now we're just reverting
struct areanode_t
{
	int		axis;		// -1 = leaf node
	float	dist;
	struct	areanode_t	*children[2];
	link_t	trigger_edicts;
	link_t	solid_edicts;
};


#define	AREA_DEPTH	4
#define	AREA_NODES	32

static	areanode_t	sv_areanodes[AREA_NODES];
static	int			sv_numareanodes;

/*
===============
SV_CreateAreaNode

===============
*/
areanode_t *SV_CreateAreaNode (int depth, vec3_t mins, vec3_t maxs)
{
	vec3_t		size;
	vec3_t		mins1, maxs1, mins2, maxs2;

	areanode_t *anode = &sv_areanodes[sv_numareanodes];
	sv_numareanodes++;

	ClearLink (&anode->trigger_edicts);
	ClearLink (&anode->solid_edicts);

	if (depth == AREA_DEPTH)
	{
		anode->axis = -1;
		anode->children[0] = anode->children[1] = NULL;
		return anode;
	}

	Vector3Subtract (size, maxs, mins);

	if (size[0] > size[1])
		anode->axis = 0;
	else anode->axis = 1;

	anode->dist = 0.5 * (maxs[anode->axis] + mins[anode->axis]);

	Vector3Copy (mins1, mins);
	Vector3Copy (mins2, mins);
	Vector3Copy (maxs1, maxs);
	Vector3Copy (maxs2, maxs);

	maxs1[anode->axis] = mins2[anode->axis] = anode->dist;

	anode->children[0] = SV_CreateAreaNode (depth + 1, mins2, maxs2);
	anode->children[1] = SV_CreateAreaNode (depth + 1, mins1, maxs1);

	return anode;
}


void SV_ClearWorld (void)
{
	SV_InitBoxHull ();
	
	memset (sv_areanodes, 0, sizeof (sv_areanodes));
	sv_numareanodes = 0;
	SV_CreateAreaNode (0, sv.worldmodel->mins, sv.worldmodel->maxs);
}
#endif


/*
===============
SV_UnlinkEdict

===============
*/
void SV_UnlinkEdict (edict_t *ent)
{
	if (!ent->area.prev)
		return;		// not linked in anywhere

	RemoveLink (&ent->area);
	ent->area.prev = ent->area.next = NULL;
}


/*
====================
SV_TouchLinks
====================
*/
void SV_TouchLinks (edict_t *ent, areanode_t *node)
{
	// this can't go in temp memory as the progs environment would stomp it
	int mark = qScratch->GetLowMark ();

	// nothing touched by default
	edict_t	**touched = (edict_t **) qScratch->FastAlloc (sv.num_edicts * sizeof (edict_t *));
	int numTouched = 0;

	// Build a new list of edicts touched by this edict since the linked list may change during touch
	// if PR_ExecuteProgram causes a new SV_LinkEdict to be called
	for (link_t *l = node->trigger_edicts.next; l != &node->trigger_edicts; l = l->next)
	{
		if (!l)
		{
			// this shouldn't happen as the list no longer changes but it seems a good sanity test all the same
			Con_Printf (PRINT_DEVELOPER, "SV_TouchLinks : null link\n");
			break;
		}

		edict_t *touch = EDICT_FROM_AREA (l);

		if (touch == ent) continue;
		if (touch->free) continue;
		if (!touch->v.touch || touch->v.solid != SOLID_TRIGGER) continue;

		if (ent->v.absmin[0] > touch->v.absmax[0] || ent->v.absmin[1] > touch->v.absmax[1] || ent->v.absmin[2] > touch->v.absmax[2] ||
			ent->v.absmax[0] < touch->v.absmin[0] || ent->v.absmax[1] < touch->v.absmin[1] || ent->v.absmax[2] < touch->v.absmin[2])
			continue;

		// link the touched ent
		touched[numTouched++] = touch;
	}

	// now walk the list of touched edicts and execute their touch functions (FIXME: this is reverse order...)
	if (numTouched)
	{
		int i;

		for (i = 0; i < numTouched; i++)
		{
			int old_self = pr_env.globalStruct->self;
			int old_other = pr_env.globalStruct->other;

			PR_RunInteraction (touched[i]->v.touch, touched[i], ent, sv.time);

			pr_env.globalStruct->self = old_self;
			pr_env.globalStruct->other = old_other;
		}
	}

	// release memory
	qScratch->FreeToLowMark (mark);

	// recurse down both sides
	if (node->axis != -1)
	{
		if (ent->v.absmin[node->axis] > node->dist) SV_TouchLinks (ent, node->children[0]);
		if (ent->v.absmin[node->axis] < node->dist) SV_TouchLinks (ent, node->children[1]);
	}
}


/*
===============
SV_FindTouchedLeafs

===============
*/
void SV_FindTouchedLeafs (edict_t *ent, mnode_t *node, float *mins, float *maxs)
{
	if (node->contents == CONTENTS_SOLID)
		return;

	// add an efrag if the node is a leaf
	if (node->contents < 0)
	{
		// there is no longer any limit on ent->num_leafs
		ent->leafnums[ent->num_leafs] = ((mleaf_t *) node) - sv.worldmodel->leafs - 1;
		ent->num_leafs++;
	}
	else
	{
		mplane_t *splitplane = node->plane;
		int sides = BoxOnPlaneSide (mins, maxs, splitplane);

		// recurse down the contacted sides
		if (sides & 1) SV_FindTouchedLeafs (ent, node->children[0], mins, maxs);
		if (sides & 2) SV_FindTouchedLeafs (ent, node->children[1], mins, maxs);
	}
}

/*
===============
SV_LinkEdict

===============
*/
void SV_LinkEdict (edict_t *ent, BOOL touch_triggers)
{
	if (ent->area.prev)
		SV_UnlinkEdict (ent);	// unlink from old position

	if (ent == sv.worldedict)
		return;		// don't add the world

	if (ent->free)
		return;

	// set the abs box
	if (SV_EdictRotated (ent, ent->v.angles))
	{
		// expand for rotation
		float v;
		float max = 0;

		for (int i = 0; i < 3; i++)
		{
			v = fabs (ent->v.mins[i]);
			if (v > max) max = v;
			v = fabs (ent->v.maxs[i]);
			if (v > max) max = v;
		}

		for (int i = 0; i < 3; i++)
		{
			ent->v.absmin[i] = ent->v.origin[i] - max;
			ent->v.absmax[i] = ent->v.origin[i] + max;
		}
	}
	else
	{
		Vector3Add (ent->v.absmin, ent->v.origin, ent->v.mins);
		Vector3Add (ent->v.absmax, ent->v.origin, ent->v.maxs);
	}

	if ((int) ent->v.flags & FL_ITEM)
	{
		// to make items easier to pick up and allow them to be grabbed off
		// of shelves, the abs sizes are expanded
		Vector2Subtract (ent->v.absmin, ent->v.absmin, float2 (15, 15));
		Vector2Add (ent->v.absmax, ent->v.absmax, float2 (15, 15));
	}
	else
	{
		// because movement is clipped an epsilon away from an actual edge,
		// we must fully check even when bounding boxes don't quite touch
		Vector3Subtract (ent->v.absmin, ent->v.absmin, float3 (1, 1, 1));
		Vector3Add (ent->v.absmax, ent->v.absmax, float3 (1, 1, 1));
	}

	// ensure that we have a valid server heap
	if (!serverHeap) serverHeap = new QHEAP ();

	// clear any previously allocated leafs
	if (ent->leafnums)
	{
		serverHeap->Free (ent->leafnums);
		ent->leafnums = NULL;
	}

	// link to PVS leafs - allocating an initial batch of temp memory so that we can expand it as required
	ent->leafnums = (unsigned short *) qScratch->Lock (__FUNCTION__);
	ent->num_leafs = 0;

	if (ent->v.modelindex)
	{
		// get a proper bounding box for this entity
		float emins[3], emaxs[3];
		model_t *model = sv.models[(int) ent->v.modelindex];

		Vector3Add (emins, ent->v.origin, model->mins);
		Vector3Add (emaxs, ent->v.origin, model->maxs);

		SV_FindTouchedLeafs (ent, sv.worldmodel->nodes, emins, emaxs);
	}

	// copy over to the entity for real if any leafs were allocated; otherwise NULL it again so that it's safe
	if (ent->num_leafs)
	{
		unsigned short *leafnums = (unsigned short *) serverHeap->Alloc (ent->num_leafs * sizeof (unsigned short));

		memcpy (leafnums, ent->leafnums, ent->num_leafs * sizeof (unsigned short));
		ent->leafnums = leafnums;
	}
	else ent->leafnums = NULL;

	qScratch->Unlock ();

	if (ent->v.solid == SOLID_NOT)
		return;

	// find the first node that the ent's box crosses
	areanode_t *node = sv_areanodes;

	while (1)
	{
		if (node->axis == -1)
			break;

		// areanode checks should use the entity abs min/max because it may be expanded
		if (ent->v.absmin[node->axis] > node->dist)
			node = node->children[0];
		else if (ent->v.absmax[node->axis] < node->dist)
			node = node->children[1];
		else break;		// crosses the node
	}

	// link it in
	if (ent->v.solid == SOLID_TRIGGER)
		InsertLinkBefore (&ent->area, &node->trigger_edicts);
	else InsertLinkBefore (&ent->area, &node->solid_edicts);

	// if touch_triggers, touch all entities at this node and decend for more
	if (touch_triggers) SV_TouchLinks (ent, sv_areanodes);
}



/*
===============================================================================

POINT TESTING IN HULLS

===============================================================================
*/

/*
==================
SV_HullPointContents

==================
*/
int SV_HullPointContents (hull_t *hull, int num, vec3_t p)
{
	float		d;
	mclipnode_t	*node;
	mplane_t	*plane;

	while (num >= 0)
	{
		if (num < hull->firstclipnode || num > hull->lastclipnode)
			Sys_Error ("SV_HullPointContents: bad node number");

		node = hull->clipnodes + num;
		plane = hull->planes + node->planenum;
		d = Vector3Dot (plane->normal, p) - plane->dist;
		num = node->children[(d < 0) ? 1 : 0];
	}

	return num;
}


/*
==================
SV_PointContents

==================
*/
int SV_PointContents (vec3_t p)
{
	int	cont = SV_HullPointContents (&sv.worldmodel->hulls[0], 0, p);

	if (cont <= CONTENTS_CURRENT_0 && cont >= CONTENTS_CURRENT_DOWN)
		cont = CONTENTS_WATER;

	return cont;
}

int SV_TruePointContents (vec3_t p)
{
	return SV_HullPointContents (&sv.worldmodel->hulls[0], 0, p);
}

//===========================================================================

/*
============
SV_TestEntityPosition

This could be a lot more efficient...
============
*/
edict_t	*SV_TestEntityPosition (edict_t *ent)
{
	trace_t	trace;

	SV_Move (&trace, ent->v.origin, ent->v.mins, ent->v.maxs, ent->v.origin, 0, ent);

	if (trace.startsolid)
		return sv.worldedict;

	return NULL;
}


/*
===============================================================================

LINE TESTING IN HULLS

===============================================================================
*/

/*
==================
SV_RecursiveHullCheck

==================
*/
BOOL SV_RecursiveHullCheck (hull_t *hull, int num, float p1f, float p2f, vec3_t p1, vec3_t p2, trace_t *trace)
{
	mclipnode_t	*node;
	mplane_t	*plane;
	float		t1, t2;
	float		frac;
	int			i;
	vec3_t		mid;
	int			side;
	float		midf;

	// check for empty
	if (num < 0)
	{
		if (num != CONTENTS_SOLID)
		{
			trace->allsolid = FALSE;

			if (num == CONTENTS_EMPTY)
				trace->inopen = TRUE;
			else trace->inwater = TRUE;
		}
		else trace->startsolid = TRUE;

		return TRUE;		// empty
	}

	if (num < hull->firstclipnode || num > hull->lastclipnode)
		Sys_Error ("SV_RecursiveHullCheck: bad node number");

	// find the point distances
	node = hull->clipnodes + num;
	plane = hull->planes + node->planenum;

	t1 = Vector3Dot (plane->normal, p1) - plane->dist;
	t2 = Vector3Dot (plane->normal, p2) - plane->dist;

	if (t1 >= 0 && t2 >= 0) return SV_RecursiveHullCheck (hull, node->children[0], p1f, p2f, p1, p2, trace);
	if (t1 < 0 && t2 < 0) return SV_RecursiveHullCheck (hull, node->children[1], p1f, p2f, p1, p2, trace);

	// put the crosspoint DIST_EPSILON pixels on the near side
	if (t1 < 0)
		frac = (t1 + DIST_EPSILON) / (t1 - t2);
	else frac = (t1 - DIST_EPSILON) / (t1 - t2);

	if (frac < 0) frac = 0;
	if (frac > 1) frac = 1;

	midf = p1f + (p2f - p1f) * frac;

	for (i = 0; i < 3; i++)
		mid[i] = p1[i] + frac * (p2[i] - p1[i]);

	side = (t1 < 0);

	// move up to the node
	if (!SV_RecursiveHullCheck (hull, node->children[side], p1f, midf, p1, mid, trace))
		return FALSE;

	// go past the node
	if (SV_HullPointContents (hull, node->children[side ^ 1], mid) != CONTENTS_SOLID)
		return SV_RecursiveHullCheck (hull, node->children[side ^ 1], midf, p2f, mid, p2, trace);

	if (trace->allsolid)
		return FALSE;		// never got out of the solid area

	//==================
	// the other side of the node is solid, this is the impact point
	//==================
	if (!side)
	{
		VectorCopy (plane->normal, trace->plane.normal);
		trace->plane.dist = plane->dist;
	}
	else
	{
		VectorSubtract (vec3_origin, plane->normal, trace->plane.normal);
		trace->plane.dist = -plane->dist;
	}

	while (SV_HullPointContents (hull, hull->firstclipnode, mid) == CONTENTS_SOLID)
	{
		// shouldn't really happen, but does occasionally
		frac -= 0.1f;

		if (frac < 0)
		{
			trace->fraction = midf;
			VectorCopy (mid, trace->endpos);
			Con_Printf (PRINT_DEVELOPER, "backup past 0\n");
			return FALSE;
		}

		midf = p1f + (p2f - p1f) * frac;

		for (i = 0; i < 3; i++)
			mid[i] = p1[i] + frac * (p2[i] - p1[i]);
	}

	trace->fraction = midf;
	VectorCopy (mid, trace->endpos);

	return FALSE;
}


/*
==================
SV_ClipMoveToEntity

Handles selection or creation of a clipping hull, and offseting (and
eventually rotation) of the end points
==================
*/
void SV_ClipMoveToEntity (trace_t *trace, edict_t *ent, vec3_t start, vec3_t mins, vec3_t maxs, vec3_t end)
{
	vec3_t		offset;
	vec3_t		start_l, end_l;
	hull_t		*hull;

	// fill in a default trace
	memset (trace, 0, sizeof (trace_t));
	trace->fraction = 1;
	trace->allsolid = TRUE;
	Vector3Copy (trace->endpos, end);

	// get the clipping hull
	hull = SV_HullForEntity (ent, mins, maxs, offset);

	Vector3Subtract (start_l, start, offset);
	Vector3Subtract (end_l, end, offset);

	// rotate start and end into the models frame of reference
	if (SV_EdictRotated (ent, ent->v.angles))
	{
		vec3_t	forward, right, up;
		vec3_t	temp;

		AngleVectors (ent->v.angles, forward, right, up);

		Vector3Copy (temp, start_l);
		start_l[0] = Vector3Dot (temp, forward);
		start_l[1] = -Vector3Dot (temp, right);
		start_l[2] = Vector3Dot (temp, up);

		Vector3Copy (temp, end_l);
		end_l[0] = Vector3Dot (temp, forward);
		end_l[1] = -Vector3Dot (temp, right);
		end_l[2] = Vector3Dot (temp, up);
	}

	// trace a line through the apropriate clipping hull
	SV_RecursiveHullCheck (hull, hull->firstclipnode, 0, 1, start_l, end_l, trace);

	// rotate endpos back to world frame of reference
	if (SV_EdictRotated (ent, ent->v.angles))
	{
		if (trace->fraction != 1)
		{
			vec3_t	a;
			vec3_t	forward, right, up;
			vec3_t	temp;

			Vector3Subtract (a, vec3_origin, ent->v.angles);
			AngleVectors (a, forward, right, up);

			Vector3Copy (temp, trace->endpos);
			trace->endpos[0] = Vector3Dot (temp, forward);
			trace->endpos[1] = -Vector3Dot (temp, right);
			trace->endpos[2] = Vector3Dot (temp, up);

			Vector3Copy (temp, trace->plane.normal);
			trace->plane.normal[0] = Vector3Dot (temp, forward);
			trace->plane.normal[1] = -Vector3Dot (temp, right);
			trace->plane.normal[2] = Vector3Dot (temp, up);
		}
	}

	// fix trace up by the offset
	if (trace->fraction != 1) Vector3Add (trace->endpos, trace->endpos, offset);

	// did we clip the move?
	if (trace->fraction < 1 || trace->startsolid) trace->ent = ent;
}

//===========================================================================

/*
====================
SV_ClipToLinks

Mins and maxs enclose the entire area swept by the move
====================
*/
void SV_ClipToLinks (areanode_t *node, moveclip_t *clip)
{
	link_t		*l, *next;
	edict_t		*touch;
	trace_t		trace;

	// touch linked edicts
	for (l = node->solid_edicts.next; l != &node->solid_edicts; l = next)
	{
		next = l->next;
		touch = EDICT_FROM_AREA (l);

		if (touch->v.solid == SOLID_NOT)
			continue;

		if (touch == clip->passedict)
			continue;

		if (touch->v.solid == SOLID_TRIGGER)
			Sys_Error ("Trigger in clipping list");

		if (clip->type == MOVE_NOMONSTERS && touch->v.solid != SOLID_BSP)
			continue;

		if (clip->boxmins[0] > touch->v.absmax[0] ||
			clip->boxmins[1] > touch->v.absmax[1] ||
			clip->boxmins[2] > touch->v.absmax[2] ||
			clip->boxmaxs[0] < touch->v.absmin[0] ||
			clip->boxmaxs[1] < touch->v.absmin[1] ||
			clip->boxmaxs[2] < touch->v.absmin[2])
			continue;

		if (clip->passedict && clip->passedict->v.size[0] && !touch->v.size[0])
			continue;	// points never interact

		// might intersect, so do an exact clip
		if (clip->trace->allsolid)
			return;

		if (clip->passedict)
		{
			if (PR_ProgToEdict (touch->v.owner) == clip->passedict)
				continue;	// don't clip against own missiles

			if (PR_ProgToEdict (clip->passedict->v.owner) == touch)
				continue;	// don't clip against owner
		}

		if ((int) touch->v.flags & FL_MONSTER)
			SV_ClipMoveToEntity (&trace, touch, clip->start, clip->mins2, clip->maxs2, clip->end);
		else SV_ClipMoveToEntity (&trace, touch, clip->start, clip->mins, clip->maxs, clip->end);

		if (trace.allsolid || trace.startsolid || trace.fraction < clip->trace->fraction)
		{
			trace.ent = touch;

			if (clip->trace->startsolid)
			{
				memcpy (clip->trace, &trace, sizeof (trace_t));
				clip->trace->startsolid = TRUE;
			}
			else memcpy (clip->trace, &trace, sizeof (trace_t));
		}
		else if (trace.startsolid)
			clip->trace->startsolid = TRUE;
	}

	// recurse down both sides
	if (node->axis == -1)
		return;

	if (clip->boxmaxs[node->axis] > node->dist) SV_ClipToLinks (node->children[0], clip);
	if (clip->boxmins[node->axis] < node->dist) SV_ClipToLinks (node->children[1], clip);
}


/*
==================
SV_MoveBounds
==================
*/
void SV_MoveBounds (vec3_t start, vec3_t mins, vec3_t maxs, vec3_t end, vec3_t boxmins, vec3_t boxmaxs)
{
	int		i;

	for (i = 0; i < 3; i++)
	{
		if (end[i] > start[i])
		{
			boxmins[i] = start[i] + mins[i] - 1;
			boxmaxs[i] = end[i] + maxs[i] + 1;
		}
		else
		{
			boxmins[i] = end[i] + mins[i] - 1;
			boxmaxs[i] = start[i] + maxs[i] + 1;
		}
	}
}


/*
==================
SV_Move
==================
*/
void SV_Move (trace_t *trace, vec3_t start, vec3_t mins, vec3_t maxs, vec3_t end, int type, edict_t *passedict)
{
	// this is the only place a moveclip_t actually ever comes from
	moveclip_t	clip;
	int			i;

	memset (&clip, 0, sizeof (moveclip_t));
	clip.trace = trace;

	// clip to world
	SV_ClipMoveToEntity (clip.trace, sv.worldedict, start, mins, maxs, end);

	clip.start = start;
	clip.end = end;
	clip.mins = mins;
	clip.maxs = maxs;
	clip.type = type;
	clip.passedict = passedict;

	if (type == MOVE_MISSILE)
	{
		for (i = 0; i < 3; i++)
		{
			clip.mins2[i] = -15;
			clip.maxs2[i] = 15;
		}
	}
	else
	{
		VectorCopy (mins, clip.mins2);
		VectorCopy (maxs, clip.maxs2);
	}

	// create the bounding box of the entire move
	SV_MoveBounds (start, clip.mins2, clip.maxs2, end, clip.boxmins, clip.boxmaxs);

	// clip to entities
	SV_ClipToLinks (sv_areanodes, &clip);
}

